Scripting – Remove blank line from file

Can anyone tell me how to remove a blank line from the end of a .txt file using NT shell scripting language.
When i pipe the contents of
for /f “tokens=2 delims=:” %%i in (‘ipconfig ^/all ^| find ^/i “ip address”‘) do echo %%i ^>> c:\temp\ipinfo.txt

I get a square character?? at the end of each IP address and a carriage return at the end of the file.
How can these be avoided or better, removed. I would like to know how to remove these for future reference.

Thanks to the whizz kid whoanswers this.
Stuart